Previously, gaseous precursor filled contrast agents had limited effectiveness because high doses of gaseous precursor materials were required to be intravascularly injected into a patient to produce contrast enhancement. Even after IV injection into a patient, not all of the gaseous precursor materials converted into stable gaseous vesicles. Gaseous precursor materials that did not convert to a gas were much less effective as a contrast agent. Sonication, agitation and hypobaric activation were developed to activate gaseous precursor filled contrast agents; however, these methods were incompletely effective and ineffective for sustained infusions of the contrast agents.
More effective methods of converting gaseous precursor materials to a gas are necessary to overcome the problems associated with the prior art. The invention is directed to these, as well as other, important ends.
The present invention describes methods of providing images of regions of a patient comprising heating a composition comprising a gaseous precursor to a temperature at or above the boiling point of the gaseous precursor; administering the composition to the patient; and scanning the patient using diagnostic imaging to obtain visible images of regions of the patient. Preferably, the gaseous precursor is a fluorinated compound. If desired, the composition may be administered to the patient as an infusion. The compositions may comprise a wide variety of additional components, including, for example, one or more of gases, gaseous precursors, liquids, oils, stabilizing materials, diagnostic agents, targeting ligands and/or bioactive agents.
The present invention also describes methods of diagnosing the presence of diseased tissues in a patient comprising heating a composition comprising a gaseous precursor to a temperature at or above the boiling point of the gaseous precursor; administering the composition to the patient; and scanning the patient using diagnostic imaging to obtain visible images of any diseased tissues in the patient. Preferably, the gaseous precursor is a fluorinated compound. If desired, the composition may be administered to the patient as an infusion. The composition may comprise a wide variety of addition components, including, for example, one or more of gases, gaseous precursors, liquids, oils, stabilizing materials, diagnostic agents, targeting ligalds and/or bioactive agents.
The present invention also describes methods of delivering bioactive agents to a patient comprising heating a composition comprising a bioactive agent and a gaseous precursor to a temperature at or above the boiling point of the gaseous precursor; and administering the composition to the patient. If desired, the methods may further comprise imaging the patient to monitor the location of the composition and/or conducting ultrasound imaging on the patient to facilitate delivery of the bioactive agents. Preferably, the gaseous precursor is a fluorinated compound. The composition may be administered to the patient as an infusion, if desired. The composition may comprise a wide variety of additional components, including, for example, one or more of gases, gaseous precursors, liquids, oils, stabilizing materials, diagnostic agents, targeting ligands and/or bioactive agents.
These and other aspect of the invention will become more apparent from the following detailed description.